Add feedback per letter of correct vs incorrect

[glazari]

Features added:

• only incorrect character in red
• if space is pressed too early, the previous word shows up as still partially untyped
• if type after the end of word, the extra letters will show up as errors (like in monkeytype)

This goes in the direction of ttyper V2 as mentioned in this issue (https://github.com/max-niederman/ttyper/issues/83)

I am not super sure about the structure of the code, so I appreciate feedback if you think there was a better way to implement this.